CS160: Lecture 19

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CS160 Lecture 19

• John Canny

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Human Learning and Help Systems

• Why study human learning for HCI?

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Why Study Human Learning?

• Ans People need to learn new applications,
  often using various forms of Help.
• Ans The way people learn should influence the
  design of help systems, and perhaps the entire
  system e.g.
• Knowledge is situated in particular contexts,
  so help should reflect that (scenarios/common
  tasks)
• Learning is layered on old knowledge in a roughly
  novice ? expert trajectory
• Learning involves a concrete ? abstract
  progression
• Fluency with abstraction varies across the
  population, esp. with degree of schooling

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Transfer Learning

• Learning is a process of building new knowledge
  using existing knowledge.
• Knowledge is not acquired butconstructed out of
  existingmaterials.
• The process of applying existingknowledge in new
  settings is called Transfer.

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Transfer Learning examples

• Youve learned basic edit commands from MS
  Notepad, and you transfer to MS Word.
• Youve installed a simple program (lets say
  Quicktime), and you transfer that knowledge to an
  MS Office installation.
• Youve done a mail merge in MS Office 2000 and
  you transfer to Office XP.

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ZPD Zone of Proximal Development

• Learning is layered and incremental.
• In societies, learners are helped by others.
• In fact learners have a zone of concepts they
  can acquire with help.
• This is the Zone of Proximal Development (ZPD).

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ZPD example

• Who knows what this is?

100k
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ZPD example

• What about this?

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Learning new applications

• Applications should be designed to fit in the
  target users ZPD it should assume the knowledge
  they typically have, and a realistic amount of
  support.
• People often learn how to use computer systems
  with the help of others, but you have to be
  realistic about this in your application context.
  

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Learning by doing

• People learn best by doing
• It marshalls all of their processors
  (cognitive, perceptual, sensori-motor).
• It forces them to apply a conceptual model to
  figure out how the system will behave.
• It allows them to observes differences between
  the systems actual behavior, and what they
  anticipate from their conceptual model. This
  helps them refine and improve their model.
• Q Whats a good example of this?

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Learning by doing

• Q Whats a good example of this?
• A Programming!
• Imagine a computer engineering course where you
  learn how to program only by being told.
• In contrast, medical schools and some CS
  departments are experimenting with Problem-Based
  Learning, where there are only projects (no
  lectures). Lecture-style material is only
  available as a library resource to help with
  project work.

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Learning and experience

• Learning is most effective when it connects with
  the learners real-world experiences.
• The knowledge that the learner already has form
  those experiences serves as a foundation for knew
  knowledge.

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Learning and transfer

• Transfer is certainly enhanced by similarity
  between the old and new contexts.
• What other factors affect transfer?

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Transfer and understanding

• Transfer depends on thorough learning in the
  first situation (learning with understanding).
• The more thorough the understanding in the first
  situation, the more easily knowledge will
  transfer.

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Understanding

• By understanding we mean that a person has a
  mental model of why a thing behaves as it does.
• This model allows the person to predict how the
  thing behaves in other situations, and to
  explain their reasons for that conclusion.

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Transfer and Generality

• Generality of existing knowledge has the learner
  already seen it applied in several contexts?

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Transfer and Motivation

• Motivation is the new knowledge useful or
  valuable?
• Motivation encourages the user to visualize use
  of the new knowledge, and to try it out in new
  situations.
• Students are usually motivated when the
  knowledge can be applied to everyday situations.

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Transfer and Abstraction

• Is the existing knowledge abstract or specific?
• Abstract knowledge is packaged for portability.
  Its built with virtual objects and rules that can
  model many real situations.
• E.g. clipart

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Metacognition

• Metacognition is the learners conscious
  awareness of their learning process.

Metacognitionhelps transfer
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Metacognition

• Strong learners carefully manage their learning.
• For instance, strong learners reading a textbook
  will pause regularly, check understanding, and go
  back to difficult passages.
• Weak learners tend toplough through theentire
  text, then realize they dontunderstand and
  startagain.

Have I learnedthis yet?
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Piaget Stages of learning

• Jean Piaget observed very systematic progression
  of knowledge in children through stages
• Sensori-motor (acting, observing, remembering)
• Semiotic or symbolic (naming things)
• Concrete operations (relationships,
  transformations)
• Propositional or formal thought

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Piaget Stages of learning

• Jean Piaget observed very systematic progression
  of knowledge in children through stages
• Sensori-motor (lt 2 years)
• Semiotic or symbolic (gt 1.5 years)
• Concrete operations (2-7,7-11 years)
• Propositional or formal thought (gt 7 years)

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Sensori-motor stage (lt 2 years)

• Conditioned behaviors, and first hand-eye
  coordination.
• Grasping, manipulating things.
• Some indirect manipulation.
• Object persistence.

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Semiotic stage (gt1.5 years)

• Children continue to play with missing objects,
  and may use gesture to invoke them.
• This soon turns to imaginary play.
• Drawing.
• Speech naming first the things that are
  present.
• Then referring to things thatare not present,
  and to the past and future.

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Concrete thought (2-7,7-11 years)

• Concrete thought a system of (real) objects,
  relationships, and operations on them.
• Children understand things by being able to
  relate them to similar things, and to predict the
  consequences of their actions.
• They can plan and act to achieve a desired
  outcome.

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Concrete thought

• But early concrete thought is still tied to
  direct experience it is not de-centered.
• E.g. children in this stage can navigate through
  their neighborhood, changing their route if
  needed.
• i.e. they can mentally model and predict the
  results of their actions.
• But they cannot indicate that route abstractly,
  say on a map.

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Concrete thought

• Concrete thought includes rich spatial and
  temporal relationships.
• Visual design is a concrete process.

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Formal thought (11 years)

• Objects and operations no longer need to relate
  to the world. Things dont need to be true or
  consistent. Thinking is a game.
• Operations are more abstract, and often
  complementary e.g. joining-separating.
• Children learn a number of principles, like
  reversibility, proportion, chance.

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Formal thought caveats

• Researchers have found that the transition to
  formal thought is not as reliable as Piaget had
  thought.
• Many features of this stage are missing in
  children who do not attend school.
• This stage corresponds with the transition from
  learning from experience (pre-school), to
  learning from texts (school).

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Thought styles

• Designers and other visually-oriented people
  usually favor concrete thought
  context-dependent, rich representations.
• Technologists and mathematically-oriented people
  favor formal thought context independent,
  sparse representations, rich consequences.

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A mismatch

• Many interface researchers (technologists) tried
  to build UI design tools using abstract interface
  specs (UIMSes)
• the designer specifies rules about the interface
  and the system finds a solution satisfying
  them.
• Real designers hated this idea. They lost control
  over spatial relationships and overall layout
  which was lost in the rules.

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Piagets progression

• The Piagetian progression can be a good model for
  the progression in learning new concepts, like
  how to use a computer program.
• Look for a Sensori-motor ? Symbolic ? Concrete ?
  Abstract progression in your own learning, and in
  your users.

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• Break

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Help models

• What kind of help works best for you?
• Do you ever read the manual?
• Is help usually where you need it?
• What are some differences between help you get
  from people and from systems?

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Types of Help

• Quick Reference
• Reminders of commoncommand names or options.
• Good to place on a card, or for small devices,
  on the device itself.
• Use a few main categoriesto avoid long search..
• E.g. for an editor, categorieslike basic,
  search/replace, load/save, etc.

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Types of Help

• Task-specific help
• User needs help on howto apply a command, orto
  complete a task.
• Can be part of a how-tosystem for common
  tasks.
• Should be easily accessiblefrom the command line
  (if text).
• Make options windows obvious and easy to find!
• E.g. add advanced button in the dialogue to
  apply any command.

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Types of Help

• Full explanation
• User wants complete understanding, to get
  bestvalue out of the application.
• This part explains the whymore than the how.
  
• E.g. How do compiler options affect performance?
  
• What are various installation components used
  for? What are the uncommon commands?
• Probably need a chapter in the help system for
  this. More system-centric than task-centric.

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Types of Help

• Tutorial
• The tutorial leads the user through a task,
  scaffolding their actions.
• Should allow users to act as well as watch
  (sandboxing).
• The best way to teach!
• More work to build into the system, but you
  should leverage your companys other effort
• E.g. most software houses conduct regular
  training sessions for customers these are ideal
  tutorial content.

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More advanced ideas

• Help is a kind of ongoing learning environment.
• Minimalist instruction (Carroll 92)is a
  learning approach
• It shows users what to do,
• then gives them realistic tasks to solve.
• It eliminates conventional exercises, tedium and
  repetition, and encourages users to explore.
• It also has extensive coverage of error recovery.
  
• - users feel confident exploring.

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More advanced ideas

• Help could be enjoyable? - at least its a
  special case of computer-supported learning..
• Training wheels (Sandboxing)
• Advanced commands are removed until user gains
  some experience with the system.
• Also some dangerous commands.
• Users explore freely in this sandbox.
• Users gained better understanding (IBM trial).

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Desiderata for help

• Availability
• Should be accessible anywhere (always include a
  help key on each major window).
• Accuracy and Completeness (hard!)
• Make sure it matches program version, and that it
  covers all the commands.
• As well as commands, common tasks should be
  described.

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Desiderata for help

• Consistency
• Content, terminology, style.
• These days, online and printed manuals are often
  the same.
• Robustness
• Help shouldnt crash if the program does (need
  another thread).
• Program exceptions can bring up the help system.

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Desiderata for help

• Flexibility
• Includes adaptation to context or user skill.
  Multi-level help is a good idea.
• Unobtrustiveness
• Shouldnt disrupt users work (like the annoying
  help characters in MS Office). A separate help
  screen is often good - supports rapid switching.

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Context-sensitive help

• Help depends on where it is used
• Tool tips ? or the windows ? symbol
• Save the user the burden of synchronizing program
  state with help system state.
• Almost always a good idea to do this.
• Just make sure the user can easily find the main
  help contents and index.

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Online tutorials

• Can be useful, BUT
• Users are not the same, some need minimal help.
• Forcing the user to execute a particular command
  is boring and annoying, and doesnt help
  learning.
• So..
• Make sure users can skip steps.
• Show users multiple ways of doing things.
• Give partial information on what to do, with more
  information available if the user requests it.

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Adaptive Help Systems

• Adaptation is a good idea because
• It avoids information that is too detailed or not
  detailed enough for a particular user.
• It avoids repetition of info the user has already
  seen.
• Can make suggestions of new ways to do tasks that
  the user may not know.
• Weaknesses
• Information can disappear (bad if the user forgot
  it too!).
• System needs to know user identity and user must
  use the system for some time.

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Initiative

• A Help system works with the user, and ideally
  should allow a spectrum of control
• Help me, tell me what to do, show me what to
  do, OK, Ill take over now
• This is calledmixed initiative.

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Initiative

• A good mixed-initiative help system requires
  links between all parts of the system including a
  tutorial.
• User should be able to take over at any time,
  then give back control.

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Design issues

• Help system design is like other parts of the
  interface.
• Start with task analysis.
• Do paper prototypes.
• Do user tests at informal and formal stages -
  look for errors.
• Use errors as the objects to guide the design
  of the help system.

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Summary

• Human Learning
• Transfer
• Zone of Proximal Development
• Meta-cognition
• Piagets stages in childrens learning.
• Concrete vs. abstract thought
• Help system design principles and types